This deck does not appear to be legal in Standard (Season from Sep 2021).
Problems: You cannot play more than 4 of: Mystical Dispute, Bonecrusher Giant // Stomp, Heartless Act, Omen of the Sea, Eliminate, Binding the Old Gods, Alrund's Epiphany, Wolfwillow Haven, Redcap Melee, Negate, Lovestruck Beast // Heart's Desire, Goldspan Dragon, Emergent Ultimatum, Duress, Cultivate, Shadows' Verdict, Ox of Agonas, Frost Bite, Elder Gargaroth, Disdainful Stroke, The Akroan War, Test of Talents, Mazemind Tome, Extinction Event, Edgewall Innkeeper, Brazen Borrower // Petty Theft, Saw It Coming, Roiling Vortex, Glass Casket, Giant Killer // Chop Down, Embercleave, Elspeth's Nightmare, Elite Spellbinder. · Not legal in this format: Mystical Dispute, Bonecrusher Giant // Stomp, Heartless Act, Omen of the Sea, Eliminate, Binding the Old Gods, Alrund's Epiphany, Wolfwillow Haven, Redcap Melee, Lovestruck Beast // Heart's Desire, Goldspan Dragon, Emergent Ultimatum, Cultivate, Shadows' Verdict, Ox of Agonas, Frost Bite, Elder Gargaroth, The Akroan War, Test of Talents, Mazemind Tome, Extinction Event, Edgewall Innkeeper, Brazen Borrower // Petty Theft, Saw It Coming, Roiling Vortex, Giant Killer // Chop Down, Embercleave, Elspeth's Nightmare, Elite Spellbinder, Shark Typhoon, Sea Gate Restoration // Sea Gate, Reborn, Scorching Dragonfire, Robber of the Rich, Rimrock Knight // Boulder Rush, Polukranos, Unchained, Koma, Cosmos Serpent, Jwari Disruption // Jwari Ruins, Jaspera Sentinel, Expressive Iteration, Yorion, Sky Nomad, Thieves' Guild Enforcer, Soul Sear, Soaring Thought-Thief, Skyclave Apparition, Showdown of the Skalds, Shatterskull Smashing // Shatterskull, the Hammer Pass, Selfless Savior, Ruin Crab, Reidane, God of the Worthy // Valkmira, Protector's Shield, Prismari Command, Merfolk Windrobber, Luminarch Aspirant, Klothys, God of Destiny, Kazandu Mammoth // Kazandu Valley, Into the Story, Galazeth Prismari, Fireblade Charger, Fervent Champion, Drown in the Loch, Drannith Magistrate, Cling to Dust, Anax, Hardened in the Forge, Alseid of Life's Bounty, Vorinclex, Monstrous Raider, Valki, God of Lies // Tibalt, Cosmic Impostor, Valiant Rescuer, Torbran, Thane of Red Fell, The Great Henge, Skyclave Shade, Seasoned Hallowblade, Quandrix Cultivator, Professor Onyx, Phoenix of Ash, Pelakka Predation // Pelakka Caverns, Kiora Bests the Sea God, Kaervek, the Spiteful, Irencrag Pyromancer, Hall Monitor, Flourishing Fox, Fire Prophecy, Esika's Chariot, Drannith Stinger, Crippling Fear, Clarion Spirit, Cinderclasm, Agadeem's Awakening // Agadeem, the Undercrypt, Toski, Bearer of Secrets, Shadowspear, Scavenging Ooze, Rip Apart, Questing Beast, Magma Opus, Lurrus of the Dream-Den, Jegantha, the Wellspring, Go Blank.